The SPC is forecasting severe thunderstorms expected over parts of the middle mississippi and ohio valleys this afternoon and tonight.
Please read the latest public
statement about this event.

Categorical Graphic

Probabilistic Tornado Graphic

Probabilistic Damaging Wind Graphic

Probabilistic Large Hail Graphic

SPC AC 221548
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1048 AM CDT THU JUN 22 2006
VALID 221630Z - 231200Z
...THERE IS A MDT RISK OF SVR TSTMS PORTIONS OF MID MS AND MUCH OF
OHIO VALLEYS...
...THERE IS A MDT RISK OF SVR TSTMS PORTIONS OF CENTRAL HIGH PLAINS
AND TX/OK PANHANDLE...
...THERE IS A SLGT RISK OF SVR TSTMS FROM CENTRAL HIGH PLAINS EWD
ACROSS MID MS VALLEY TO NY/PA...
...SYNOPSIS...
BROAD TROUGH CENTRAL U.S. WITH UPPER HIGH PARKED OVER CA. WHILE
STRONGEST WIND FIELDS REMAIN ACROSS NRN STATES...A COUPLE MID
IMPULSES HAVE EMERGED FROM WEDNESDAYS CONVECTIVE ACTIVITY. MCV
TRACKING EWD ACROSS NRN IL CURRENTLY DRIVING EARLY STORM DEVELOPMENT
THAT AREA. UPSTREAM MID LEVEL TROUGH ERN KS WILL MOVE ACROSS MO AND
MID MS VALLEY THIS AFTERNOON. A WEAK TROUGH IN THE WNWLY FLOW
CURRENTLY CROSSING CENTRAL ROCKIES...NOTED IN W/V IMAGERY...WILL
ENHANCE SHEAR AND STORM POTENTIAL E SLOPES THIS AFTERNOON.
...MID MS AND OH VALLEY...
MORNING SOUNDINGS AND SURFACE ANALYSIS DEPICT A VERY MOIST/UNSTABLE
AIRMASS IN PLACE TO THE S AND E OF SURFACE BOUNDARIES THAT EXTEND
FROM LWR MI SWWD ACROSS NRN IL TO MO. WITH MID LEVEL LAPSE RATES OF
7C/KM AND MUCH OF AREA RECEIVING STRONG HEATING...MLCAPES OF 3000
J/KG WILL BE COMMON BY MID AFTERNOON. THE ENHANCED MID LEVEL SHEAR
AND LARGE SCALE ASCENT AHEAD OF THE TWO MID LEVEL IMPULSES CENTRAL
U.S. SUPPORT A VERY ACTIVE SEVERE THUNDERSTORM DAY FROM MID MS
VALLEY EWD ACROSS OH VALLEY. SUFFICIENT SHEAR COUPLED WITH THE
INSTABILITY TO SUPPORT BOTH SUPERCELLS AMD ORGANIZED LINES WITH
LARGE HAIL AND DAMAGING WINDS PRIMARY THREAT. ISOLATED TORNADOS
COULD OCCUR IN FAVORABLY ENHANCED SHEAR VICINITY BOUNDARIES.
FURTHER E ACROSS PA/NY CLOUDS ARE DISSIPATING WHICH WILL ALLOW
STRONG DESTABILIZATION AS LOW LEVEL MOISTURES CONTINUES SPREADING E.
30-35 KT OF SHEAR AND MLCAPES UPWARDS TO 2000 J/KG SUFFICIENT FOR
SEVERE POTENTIAL...WIND/HAIL...WITH STORMS THAT DEVELOP DURING THE
AFTERNOON.
...CENTRAL HIGH PLAINS...
LOW LEVEL MOISTURE HAS WORKED WWD TO FRONT RANGE CENTRAL ROCKIES AND
WITH APPROACH OF MID LEVEL TROUGH BOTH INSTABILITY AND SHEAR WILL
SUPPORT AN ACTIVE SEVERE DAY FROM ERN CO SEWD TO TX/OK PANHANDLES.
NEAR FULL HEATING WILL ALLOW STORM INITIATION BY EARLY AFTERNOON
HIGHER TERRAIN AS MLCAPES INCREASE TO 2000 J/KG. STORMS THEN WILL
MOVE E/SEWD INTO INCREASINGLY FAVORABLE VEERING SHEAR ENVIRONMENT
AND STRONGER INSTABILITY. SUPERCELLS ARE EXPECTED WITH LARGE
HAIL/DAMAGING WINDS PRIMARY THREAT. HOWEVER SHEAR AND FAVORABLY LOW
LFC'S SUPPORT A TORNADO THREAT AS WELL. SEVERE THREAT WILL
PROPAGATE SEWD AND CONTINUE AFTER DARK.
...SERN AZ...
HAVE ADDED ISOLATED DAMAGING WIND THREAT THIS AREA AS PW'S HAVE
INCREASED TO NEAR AN INCH AND STEEP LAPSE RATES REMAIN. STORMS OVER
HIGHER TERRAIN WILL PROPAGATE INTO DESERTS VALLEYS LATE THIS
AFTERNOON AND WITH DCAPES AROUND 1500 J/KG ISOLATED DOWNBURSTS ARE
LIKELY.
..HALES/GUYER.. 06/22/2006
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z